In the prior art, and particularly British Pat. No. 748,727, there is described an inversion polymerization process. The process described therein comprises forming an initial conversion of monomer to polymer of up to 20% by mass polymerization of the monomer in the presence of a suitable catalyst. In this portion of the polymerization, the monomer is the continuous phase. Thereafter, sufficient water is added to the polymerization system to cause a phase inversion wherein the water becomes the continuous phase forming a dispersion of the unpolymerized monomer in the water. This dispersion is then polymerized to convert essentially all of the remaining monomer to solid polymer. However, the disadvantage of such process is that polymer buildup on the walls of the reactor or "poly" is excessive and requires cleaning after each batch or run is made. Further, after several runs are made it is necessary for an operator to enter the reactor and scrape the buildup from the surfaces which presents a health hazard as well as economic difficulties.
In U.S. Pat. No. 3,706,722 there is described an inversion polymerization process for producing polymers having improved uniformity in porosity, size and structure. This the patentees accomplish by incorporating a nonionic, monomer-soluble surface active agent in the initial continuous monomer phase. While producing a more porous polymer, the polymer buildup is still a problem and detracts from the use of said process on a commercial basis. This is particularly true when producing polymers and copolymers of vinyl chloride where the buildup problem and health hazard are most acute.
Accordingly, there is a great need to produce polymers having uniform porosity, size and structure by the inversion polymerization procedure which procedure would substantially eliminate polymer buildup.